CN109145473A - A kind of infall process prediction technique of vertical drainage plate consolidation saturated soft soil - Google Patents
A kind of infall process prediction technique of vertical drainage plate consolidation saturated soft soil Download PDFInfo
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Abstract
The invention discloses a kind of infall process prediction techniques of vertical drainage plate consolidation saturated soft soil, belong to foundation treatment technology research field in geotechnical engineering.It has comprehensively considered non-linear large deformation, material parameter, boundary condition, the vacuum load changed over time and preloading, unloading/reloading, vertical shaft are not punched, vacuum is along factors such as well loss, Non-Darcy's flow, vertical and radial two dimensional fluid flows, efficiently reduce error, computational accuracy is improved, calculating advantage this for big strain problems becomes apparent from；The prediction technique simple and flexible simultaneously, constitutive relation can be according to user's wish flexible settings, this, which solves the problems, such as that Consideration is not comprehensive, and material parameter is selected improper leads to that error calculated is larger, it is practical to be difficult under complex engineering environment.Therefore the present invention can be used for that R&D institution's experimental study and engineering site is assisted to consolidate prediction.
Description
Technical field
The invention belongs to foundation treatment technology research fields in geotechnical engineering, more particularly, to a kind of vertical drainage plate
Consolidate the infall process prediction technique of saturated soft soil.
Background technique
The widely distributed weak soil for having the various origin causes of formation in the area such as China coast is built structures on soft soil foundation and is needed in advance
Reinforcement Measures are taken, ground is made to reach intensity requirement, deformation requirements, stability requirement, water penetration requirement etc..Discharging consolidation
Method is one of common method of soft soil foundation.Vertical drain method in ground by being arranged plastic draining board, sand drain or bag
Then the vertical drainages such as sand loading well channel carries out piling prepressing or preloading combined vacuum precompressed, native pore water is made to accelerate row
Out, ground settles simultaneously, to make foundation strength step up within the relatively short time, to meet construction requirements.By
In plastic draining board with drainage effect is good, construction quality is easily controllable, construction disturbance is small, speed of application is fast, high-strength light is resistance to
It waits so long plurality of advantages, vertical plastic draining board is set in ground in recent years and gradually replaces sand drain, it has been widely applied
In the various fields of civil engineering.Accelerate saturated soft soil consolidation for vertical plastic draining board, passes through meter before formal construction
It calculates and carrys out Accurate Prediction process of consolidation, and then take most suitable design and arrangement and method for construction particularly necessary.
Currently, relevant technical staff in the field has done some researchs, mostly by using different analytic method meters
The infall process of corresponding vertical drainage plate consolidation saturated soft soil is calculated, influence power is higher as Indraratna 2005 is parsed
Solution, 2007 analytic solutions of Rujikiatkamjorn, 2012 analytic solutions of Geng, but these analytic solutions all have considerable hypothesis
Condition, cannot consider that simultaneously large deformation, material parameter are non-linear, the vacuum load that changes over time and preloading, unloading/again plus
Load, vertical shaft is not punched, vacuum is along factors such as well loss, Non-Darcy's flow, vertical and radial two dimensional fluid flows, thus in practical projects
Using biggish error can be generated；There are also some business finite element software modeling and analysis methods, but finite element analysis is in this structure
Relation Parameters selection is upper inflexible, therefore tends not to meet user's needs.Therefore, there is develop a kind of essence for this field
Spend the technical need of the infall process prediction technique of vertical drainage plate consolidation saturated soft soil higher, easy to use.
Summary of the invention
Aiming at the above defects or improvement requirements of the prior art, the present invention provides a kind of vertical drainage plate consolidation saturation is soft
Soil infall process prediction technique, comprehensively considered non-linear soil model constitutive relation, material parameter, boundary condition, with
The factors such as the vacuum load of time change and preloading, Non-Darcy's flow, vertical and radial two dimensional fluid flow, efficiently reduce error,
Improve computational accuracy, calculating advantage this for big strain problems becomes apparent from, can be used for assisting R&D institution's experimental study and
Engineering site consolidation prediction.
To achieve the goals above, the present invention provides a kind of infall process predictions of vertical drainage plate consolidation saturated soft soil
Method includes the following steps:
The constitutive relation data point of the soil model of saturated soft soil, boundary condition, geometrical condition, at any time is arranged in step 1
The vacuum load of variation and preloading, Non-Darcy's flow index and calculating termination condition；
Step 2, it is predetermined by the soil model is divided into inside and outside smear zone according to the constitutive relation data point of the first step
The annular element of radial, vertical number, and calculate initial volume, initial void ratio and the final void ratio of the unit；
Step 3, according to the data that step 2 obtains, the angular coordinate of computing unit, node coordinate, element thickness, certain moment
Vacuum load and preloading, consider after vacuum leak the vacuum of each position, the total stress of the unit, effective stress, infiltration in well
Saturating coefficient, pore water pressure, gross head, hydraulic gradient and volume percolation flow velocity；
Step 4, the incremental time for taking the minimum value in the incremental time of all units to calculate as a time step, in turn
Obtained incremental time is superimposed with current consolidation time to obtain new total consolidation time；
Step 5 calculates the volume seepage discharge for flowing in and out unit, Jin Erke according to volume percolation flow velocity and incremental time
The new volume of computing unit；New unit void ratio is obtained according to unit initial volume, initial void ratio and the new volume of unit；Root
The angular coordinate, node coordinate, element thickness of unit can be calculated according to the new volume of unit；And then by all element thicknesses be superimposed with
New soil body height is obtained, the difference of initial soil body height and new soil body height is settling amount；
Soil body primary consolidation final settlement, the ratio of settling amount and final settlement is calculated by final void ratio in step 6
Value is the sedimentation average degree of consolidation of the soil body；Judge whether the total consolidation time obtained or the average degree of consolidation reach scheduled
Total consolidation time or scheduled average degree of consolidation, if reaching, end loop is calculated, and otherwise goes to step 3.
Further, in step 1, soil layer elemental height H is set0；Soil particle specific gravity Gs；Vertical drainage plate squeezes into soil layer depth
Spend Ld；Gully equivalent redius rw；Smear zone equivalent redius rs；Gully Equivalence effects radius re；Boundary condition is set, i.e., respectively
Strains or the iso-stress conditions such as whether boundary drains, coboundary is；Specify initial overlying burden or initial void ratio；Seepage flow can take
It from Darcy's law or disobeys, i.e. setting Non-Darcy's flow index β；By volume of data point to setting constitutive relation, setting is again
Consolidate index CrTo handle unloading/reloading；Provide soil model top and bottom hydrostatic level height；Pass through volume of data point
To providing vacuum load and preloading changes with time relationship；Provide the reduction form of vacuum in well；With the degree of consolidation or consolidation
Time form setting calculates termination condition.
Further, in step 2, soil model is first subjected to dividing elements according to the data of the first step, is vertically divided
Number of unit is Rj, the number of unit radially divided is Ri, the number of unit wherein radially divided in smear zone is Rs, smear zone
The number of unit that outer radial divides is Ri-Rs, and provide smear zone osmotic coefficient ratio kh/ks；According to cell geometry computing unit
Initial volume V0,i；The initial total stress of top layer's unit is obtained according to initial overlying burden and soil body self weight, is consolidated still in t < 0
Do not start, therefore the difference of initial total stress and hydrostatic pore pressure is initial effective stress, cyclic approximation obtains on compression curve
It is successively calculated from top to bottom to the void ratio and effective stress to match by upper unit void ratio updating unit saturated unit weight
Obtain the initial void ratio and initial effective stress of whole units；Then the final effective stress of computing unit and final void ratio, when
It is believed that soil body primary consolidation is completed when the excess pore water pressure of each unit no longer dissipates, i.e., after plus generalized load and it is initial effectively
Stress superposition calculates to obtain final effective stress, and then obtains the final effective stress of unit after the completion of soil solidifying, then root again
The final void ratio of unit is obtained according to soil body-shield machine system.
Further, the final thickness of unit is calculated according to the following formula:
L in formulafFor unit final thickness；LoFor unit original depth；efFor unit final void ratio, eoIt is initial for unit
Void ratio；By the final height of the final thickness of all units soil body that is overlapped that you can get it, the elemental height of the soil body with most
Difference between whole height is soil body final settlement.
Further, in step 3, it is assumed that soil model outmost turns annular element cross section in consolidation process remains square
Shape, ignores horizontal strain, and remaining element cross section after consolidation starts is parallel trapezoidal of vertical edges, then the angle point of each unit
Vertical coordinate is calculated according to following formula:
Wherein, j=1,2,3 ..., Rj；I=1,2,3 ..., Ri；
Indicate the volume of t moment unit ij,
riFor the radial coordinate of node, Δ riFor the radial width of unit,
r1=ri-Δri/ 2, r2=ri+Δri/2；
The vertical coordinate of each node is calculated according to following formula:
The thickness of unit is calculated by following formula:
The preloading at certain moment is uniformly distributed under the conditions of iso-stress, can be obtained by following formula:
t2、t1By when m- payload data point to acquisition；
For equal strained conditions, preloading adjusted is calculated according to following formula:
Wherein, zavgFor soil body average height,
η is the ratio of total preloading and the preceding total preloading of adjustment after adjustment,
For radial markings be i unit t moment top preloading；Circulation adjustment is until the strain standard such as satisfaction；
The serious null value of the well at certain moment is calculated according to following formula:
tv1、tv2By when m- vacuum data point to acquisition；
Consider vacuum along well loss, generally assume that vacuum is reduced from Jing Ding to lower linear, then in well certain position vacuum
Value is calculated according to following formula:
Wherein, j is vertical drainage Board position vertex ticks, and k is vacuum reduction coefficient, LdDepth is squeezed into for vertical drainage plate
Degree.
When not applying vacuum, the total stress at node i j is calculated according to following formula:
When a vacuum is applied, the total stress at node i j calculates are as follows:
In formula,For total stress of the unit ij in total consolidation time t；γwFor the severe of water；It is unit im total
Soil body saturated unit weight when consolidation time t；htFor hydrostatic level height；The soil body for being unit ij in total consolidation time t saturation
Severe；qoFor initial overlying burden, and the soil body has consolidated completion when t < 0 under this load,For the list for being designated as i under radial direction
Member preloading at the top of the soil body of t moment；
The void ratio of unit is calculated according to following formula:
In formula,For void ratio of the unit ij in total consolidation time t+ Δ t；eo,jFor the initial void ratio of unit j；For volume of the unit ij in total consolidation time t+ Δ t；V0,iThe unit initial volume of i is designated as under；
The effective stress of unitAnd infiltration coefficientIt is closed according to the void ratio of unit at this time in this structure of multistage linear
It is that interpolation obtains in curve；
Pore pressureIt is the difference of total stress and effective stress:
Super quiet pore pressure is the difference of pore pressure Yu hydrostatic pore pressure:
Deformation makes vertical infiltration coefficientDeviate original vertical infiltration coefficientIt is oval using infiltration coefficient,'s
Value calculates are as follows:
WhereinIt is the horizontal direction of t moment unit ij and the angle of original vertical direction；
Equivalent coefficient of permeability is vertical equivalent between j+1 for describing seepage flow between unit, node i j and node i between unit
Infiltration coefficientExpression are as follows:
In top boundaryBottom boundary
If seepage flow follows Darcy's law and non-darcy index stream mode, from unit ij to unit i, the vertical body of j+1
Product flow rateIt can be expressed generally as:
Wherein β is Non-Darcy's flow index, β=1 when seepage flow obeys Darcy's law；
Vertical hydraulic gradientExpression are as follows:
The gross head of each node is calculated according to following formula:
If lower limits can drain, lower boundary hydraulic gradient:
Otherwise
If upper bound can drain, the coboundary hydraulic gradient when not applying vacuum:
When only applying vacuum in well:
When applying in well with vacuum at the top of the soil body:
In formula,Refer to vacuum values at the top of the soil body；If upper bound does not drain
Radial Flow rate between unit ij and i+1, j:
In gully
Gully is permeated completely for one, and when not adding vacuum, vertical shaft is with soil body intersection hydraulic gradient:
Hydraulic gradient when a vacuum is applied:
In formula,Refer to the vacuum values in well at certain position；
Gross head is taken as h in partial penetration gullyt；To H not plus when vacuum0-z0,1,j≤LdPart, hydraulic gradient are as follows:
To H0-z0,1,j> LdPart,Matching test (27) modifies formula (28) when applying vacuum；
In gully and soil body intersection Radial Flow rate calculations are as follows:
Seepage flow does not occur for soil body outer boundary, i.e.,
Further, in step 4, the incremental time of each time step is calculated according to the following formula:
In formula,To calculateThe compressed coefficient；ef,jFor unit ij final void ratio；
It is searched on each unit to find the minimum value of Δ t, the use of the minimum value is then that all units timely update
Cell parameters.
Further, in step 5, the public affairs of new unit volume are obtained according to the volume percolation flow velocity and incremental time of unit
Formula is as follows:
After obtaining new unit volume, new unit void ratio is calculated according to formula (11)；According to formula (2), (3), (4) meter
New angular coordinate, node coordinate and element thickness；Obtained element thickness is superimposed available new soil body height, newly
Soil body height and initial soil body height between difference be settling amount.
Further, in step 6, the parameter in saturated soft soil consolidation process includes void ratio distribution, soil body settling amount, soil
The total volume seepage discharge of body height, each unit coordinate, each unit thickness, pore water pressure, the soil body, average super quiet pore pressure and
Average degree of consolidation changes with time.
In general, compared with prior art, the infall process of vertical drainage plate consolidation saturated soft soil provided by the invention
Prediction technique mainly has the advantage that
(1) non-linear relation of material is considered by the constitutive relation of flexible setting soil model；By being arranged at any time
Between the vacuum load that changes and preloading consider Practical Project loaded condition；Difference inside and outside the smear zone involved in calculating process,
Vertical shaft do not punch, Non-Darcy's flow seepage flow, vertical and Radial Flow Through Porous Media, vacuum leak etc.；Therefore this method comprehensively considered large deformation,
Material parameter is non-linear, boundary condition, vacuum load and preloading variation, vacuum leak, film coating perfonnance, vertical shaft are not punched, non-reaches
The factors such as western stream, two dimensional fluid flow, efficiently reduce error, improve computational accuracy；
(2) the prediction technique simple and flexible, it is easy to accomplish, calculating section can be described and be protected by computer program form
It deposits, later without change, parameter needed for user only needs input to calculate, computational efficiency is high, and is conducive to complex engineering condition
Under application；
(3) this method can accurately predict the infall process of vertical drainage plate consolidation saturated soft soil, be at subsequent ground
Reason, science carry out Design of Soft Soil and construction provides valuable guidance；
(4) use when calculating Δ t first two of step 4 can be realized numerical stability, and Section 3 is ensured for any
The variation of given incremental time, each unit volume strain does not exceed corresponding ef0.1%；
(5) present invention has comprehensively considered that large deformation, material parameter be non-linear, boundary condition, the vacuum lotus changed over time
Carry and preloading, unloading/reloading, vertical shaft do not punch, vacuum along well loss, Non-Darcy's flow, vertical and radial two dimensional fluid flow etc. because
Element efficiently reduces error, improves computational accuracy, and calculating advantage this for big strain problems becomes apparent from；This is pre- simultaneously
Survey method simple and flexible, constitutive relation can be according to user's wish flexible settings, this is solved, and Consideration is not comprehensive and material
Material parameters selection is improper to lead to that error calculated is larger, is difficult to practical problem under complex engineering environment.Therefore the present invention
Can be used for that R&D institution's experimental study and engineering site is assisted to consolidate prediction.
Detailed description of the invention
Fig. 1 is the infall process prediction technique for the vertical drainage plate consolidation saturated soft soil that better embodiment of the present invention provides
Flow chart；
Fig. 2 (a) is the soil model that the infall process prediction technique of the vertical drainage plate consolidation saturated soft soil in Fig. 1 is related to
Schematic diagram in original state；After applying vacuum load and preloading, consolidation starts, and cell cross-section becomes vertical edge from rectangle and puts down
Capable is trapezoidal, as shown in Fig. 2 (b).
Fig. 3 (a), (b) are that constitutive relation data point (respectively corresponds soil to schematic diagram outside the smear zone that can be provided by user
Compressibility, permeability).
Fig. 4 is the comparison of the soil solidifying degree that the present invention predicts and test measured data.
Fig. 5 (a) is the comparison of the soil solidifying degree that the present invention predicts and analytic solutions calculated result；Fig. 5 (b) is the present invention
The comparison of the soil body predicted averagely super quiet pore pressure and analytic solutions calculated result.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to the accompanying drawings and embodiments, right
The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and
It is not used in the restriction present invention.As long as in addition, technical characteristic involved in the various embodiments of the present invention described below
Not constituting a conflict with each other can be combined with each other.
In present embodiment, the vertical drainage plate accelerate saturated soft soil consolidation process prediction technique mainly include with
Lower step:
The soil model constitutive relation data point of saturated soft soil, boundary condition, geometrical condition, at any time is arranged in step 1
The vacuum load of variation and preloading, Non-Darcy's flow index, calculating termination condition etc..Specifically, the soil body mould of saturated soft soil is set
Height, drain bar driving depth, the boundary condition of model, the boundary hydrostatic level height, soil particle specific gravity, soil body-shield machine system of type
Data point and calculating termination condition (scheduled total consolidation time or scheduled average degree of consolidation).Depth is squeezed into for drain bar
Degree, may be configured as punching soil layer or squeezes into any depth.For the boundary condition of soil model, model top and bottom can be divided
Not being set as permeable perhaps impervious boundary top surface may be configured as iso-stress or waits strained conditions.For the vacuum lotus of application
It carries and preloading, how is vacuum in the vacuum load that can be respectively set plus change over time in well and at the top of the soil body, and setting well
Reduction, preloading are applied to coboundary and with coboundary movements.Soil body-shield machine system refers between soil body void ratio and effective stress
Relationship and infiltration coefficient and void ratio between relationship.Soil body-shield machine system can both use piecewise linearity with data point
Dull form input, can also directly input nonlinear constitutive relation equation, can fully comply with user's wish.It calculates and terminates item
Part can be total consolidation time or average degree of consolidation reaches designated value.
Step 2 by the soil model to be divided into the unit of vertical, radial predetermined number inside and outside smear zone, and calculates
Initial volume, initial void ratio and the final void ratio of the unit.Specifically, the soil model is divided into from the bottom up
The unit of the vertical predetermined number of equal original depths；By the soil model from the interior diameter for being divided into equal in width in smear zone outward
The unit of the radial predetermined number of equal in width to outside the unit of predetermined number, smear zone.Unit initial volume is according to cell geometry
It calculates；The initial void ratio of unit can directly be set, can also be by being calculated, when by being calculated, according to first
Beginning overlying burden, topsoil void ratio, specific gravity of soil partical and soil body-shield machine system can determine soil body initial effective stress, further according to
Constitutive relation determines initial void ratio；After the completion of consolidation, the final effective stress of unit is initial effective stress and adds after final
The sum of generalized load, then according to the soil body constitutive relation it can be concluded that unit final void ratio.
Step 3, the successively angular coordinate of computing unit, node coordinate, element thickness, the vacuum load and heap at certain moment
It carries (uniformly distributed for iso-stress condition preloading, for waiting strained conditions to be related to Stress relief to meet uniform settlement), consider vacuum
The vacuum values of each position, the total stress of the unit, effective stress, infiltration coefficient and volume percolation flow velocity in well after loss.It is first
First, it is assumed that the bottom surface of soil model is fixed and the face where coordinate origin, vertical drainage plate central axes and soil model bottom surface
Intersection point is coordinate origin, and the geometric center of each unit is the node of the unit, and the vertical distance of node to coordinate origin is section
The vertical coordinate of point, the radial distance of node to coordinate origin are the radial coordinate (radial coordinate is fixed) of the node, the right side of unit
Vertical angle point vertical coordinate apart from referred to as unit of the upper angle point to coordinate origin；The vacuum values at certain moment and overlying burden by with
Family it is given when m- vacuum curve, when m- load curve carry out interpolation and obtain, preloading is uniformly distributed under the conditions of iso-stress, for etc.
Strained condition redistributes preloading according to settlement difference under conditions of guaranteeing that total preloading value is constant；Think that vacuum is along well in well
Linear reduction is reduced in the form of certain given function, and functional form can be set；The total stress of unit is corresponding node top
The sum of soil body self weight and overlying burden；Effective stress is acquired by soil body void ratio with soil body-shield machine system；Infiltration coefficient passes through
Soil body void ratio is acquired with soil body-shield machine system；The pore water pressure of unit is between the total stress and the effective stress
Difference；Gross head is superimposed to obtain by level head and pore pressure, and application position direct for vacuum, vacuum should be superimposed into pore pressure；Root
According to hydrostatic level height, gross head, the height of the soil body, vacuum, the radial coordinate of node, the vertical coordinate of node, cell geometry, side
Boundary's condition, Non-Darcy's flow index and infiltration coefficient calculate the volume percolation flow velocity of obtaining unit.
Step 4 takes the minimum value in the incremental time of all units to calculate the incremental time of step as one, and then will
Obtained incremental time is superimposed to obtain new total consolidation time with current consolidation time.The calculating step of each unit has it
Corresponding incremental time takes the minimum value in the corresponding incremental time of all units to calculate the incremental time of step as one, so
Obtained incremental time and current consolidation time are overlapped afterwards, to obtain new total consolidation time.
Step 5, it is assumed that soil body particle and water is all incompressible and unit in soil be permanently retained in the unit, foundation
Volume percolation flow velocity calculates the seepage discharge for flowing in and out unit, and then calculates the new volume of unit；According to initial body at the beginning of unit
Product, initial void ratio and the new volume of unit obtain new unit void ratio；According to the angular coordinate of the new volume computing unit of unit,
Node coordinate and element thickness, and then new soil body height can be obtained, initial soil body height subtracts the soil body height newly obtained
The corresponding settling amount of as described consolidation time.
The final settlement of step 6, soil body primary consolidation can be calculated by final void ratio, settling amount and final settlement
The ratio of amount be the soil body average degree of consolidation, export saturated soft soil consolidation process in parameter change over time as a result, and sentencing
Whether the disconnected total consolidation time obtained or the average degree of consolidation reach scheduled total consolidation time or scheduled average solid
Knot degree terminates to calculate, otherwise goes to step 3 if reaching.Parameter in the consolidation process of saturated soft soil includes hole score
The change at any time such as cloth, soil body settling amount, soil body height, each unit pore water pressure, average super quiet pore pressure, average degree of consolidation
Change.
Below in conjunction with two specific embodiments come the present invention is described in further detail, and prove this method have compared with
High precision of prediction.
Specific embodiment one: not plus vacuum, constitutive relation it is non-linear, constitutive relation, large deformation are described with formula form
Indraratna in 2005 is described to be tested using the indoor radial consolidation that large-scale consolidation apparatus carries out, and chooses it herein
In one, this method calculated result is compared with laboratory test results.
Step 1: Soil Parameters are arranged and establish model according to example actual conditions.Calculate needed for parameter by
It tests and provides in 2005 text of Indraratna, be specifically provided that soil body elemental height 0.870m；Consider self weight and Gs=
2.7；It is identical as soil body height to push up bottom boundaries head；Vertical drainage plate equivalent redius rw=0.033m；Equivalence effects radius re=
0.225m；Smear zone radius rs=0.1m；Setting vertical shaft can drain, and coboundary can not drain；Coboundary is to wait strained conditions；
Initial vertical effective stress σv′i=50kPa, initial void ratio ei=0.95；Seepage flow obeys Darcy's law, initial radial infiltration system
Number khi=4.0e-10m/s, smear zone osmotic coefficient ratio kh/ks=1.5；Use logarithm constitutive model and Cc=0.29, Ck=
0.45, constitutive relation formula can be extracted according to the relevant parameter of the logarithm constitutive model:Instantaneous herk Q=50kPa,
Do not apply vacuum, it is that the degree of consolidation reaches 99.99% that setting, which calculates termination condition,.
Model, is vertically divided into 20 units by second step, and smear zone is radially divided into 2 units, smear zone outer radial
It is divided into 18 units, and the initial volume of computing unit, initial void ratio and final void ratio.Unit initial volume according to
The geometric dimension of each unit is calculated, and initial void ratio and final void ratio calculated result are as follows:
The final thickness of unit can be calculated according to the following formula:
L in formulafFor unit final thickness；LoFor unit original depth；efFor unit final void ratio, eoIt is initial for unit
Void ratio.By the final height of the final thickness of all units soil body that is overlapped that you can get it, the elemental height of the soil body with most
Difference between whole height is soil body final settlement.
Third step, calculate each unit angular coordinate, node coordinate, element thickness, the vacuum load at certain moment and preloading,
Total stress, effective stress, infiltration coefficient, gross head, hydraulic gradient and volume percolation flow velocity.
The vertical coordinate of the angle point of each unit is calculated according to following formula:
J=1,2,3 ..., Rj；I=1,2,3 ..., Ri；The volume of moment unit ij, riIt is sat for the radial direction of node
Mark, Δ riFor the radial width of unit.
The vertical coordinate of each node is calculated according to following formula:
The thickness of unit is calculated by following formula:
The preloading at certain moment is uniformly distributed under the conditions of iso-stress, can be obtained by following formula:
t2, t1By user define when m- payload data point to acquisition, apply in this embodiment instantaneous
Load 50kPa can be described by (0,0), (0,50) two data point.
The present embodiment soil body coboundary is to wait strained conditions, and preloading adjusted is calculated according to following formula
Wherein zavgIt, can be according to the height of each cylinder for soil body average heightIt is average to carry out volume weighting
It acquires；η is the ratio of total preloading and the preceding total preloading of adjustment after adjustment,For radial markings be i unit at the top of t moment
Preloading；Circulation adjustment is until the strain standard such as satisfaction.
The present embodiment does not apply vacuum, therefore does not need to calculate the vacuum values at each moment.
The present embodiment is calculated due to not applying vacuum, the total stress at node i j according to following formula:
In formula,For total stress of the unit ij in total consolidation time t；γwFor the severe of water；It is unit im total
Soil body saturated unit weight when consolidation time t；htFor hydrostatic level height；The soil body for being unit ij in total consolidation time t saturation
Severe.qoFor initial overlying burden, and the soil body has consolidated completion when t < 0 under this load,For the list for being designated as i under radial direction
Member preloading at the top of the soil body of t moment.
The void ratio of unit is calculated according to following formula:
In formula,For void ratio of the unit ij in total consolidation time t+ Δ t；eo,jFor the initial void ratio of unit j；For volume of the unit ij in total consolidation time t+ Δ t；V0,iThe unit initial volume of i is designated as under.
The effective stress of unitAnd infiltration coefficientIt is closed according to the void ratio of unit at this time in this structure of multistage linear
It is that interpolation obtains in curve.
Pore pressureIt is the difference of total stress and effective stress:
Super quiet pore pressure is the difference of pore pressure Yu hydrostatic pore pressure:
Deformation makes vertical infiltration coefficientDeviate original vertical infiltration coefficientIt is oval using infiltration coefficient,'s
Value is calculated as
WhereinIt is the horizontal direction of t moment unit ij and the angle of original vertical direction.
Equivalent coefficient of permeability is vertical equivalent between j+1 for describing seepage flow between unit, node i j and node i between unit
Infiltration coefficientIt is expressed as
In top boundaryBottom boundary
If seepage flow follows Darcy's law and non-darcy index stream mode, from unit ij to unit i, the vertical body of j+1
Product flow rateIt can be expressed generally as
Wherein β is Non-Darcy's flow index, and seepage flow obeys Darcy's law therefore β=1 in this embodiment.
Vertical hydraulic gradientIt is expressed as
The gross head of each node is calculated according to following formula:
Lower limits can not drain, lower boundary hydraulic gradientUpper bound does not drain then coboundary hydraulic gradient
In other embodiments, if lower limits can drain, lower boundary hydraulic gradient:
Otherwise
If upper bound can drain, the coboundary hydraulic gradient when not applying vacuum:
When only applying vacuum in well:
When applying in well with vacuum at the top of the soil body:
In formula,Refer to vacuum values at the top of the soil body；If upper bound does not drain
Corresponding expression formula is used for computing unit ij and i+1 below, the Radial Flow rate between j:
In gully
It is complete infiltration gully in the present embodiment, not plus vacuum, vertical shaft are with soil body intersection hydraulic gradient:
Gross head is taken as h in partial penetration gullyt；To H not plus when vacuum0-z0,1,j≤LdPart, hydraulic gradient are as follows:
To H0-z0,1,j> LdPart,Matching test (27) modifies formula (28) when applying vacuum；
It is in gully and soil body intersection Radial Flow rate calculations
Seepage flow does not occur for soil body outer boundary, i.e.,
4th step, the incremental time for taking the minimum value in the incremental time of all units to calculate as a time step, into
And obtained incremental time is superimposed with current consolidation time to obtain new total consolidation time.Specifically, it counts according to the following formula
Calculate the incremental time of each time step:
In formula, whereinTo calculateThe compressed coefficient；efjFor unit ij final void ratio.First two of equation
It is that explicit time-integration method is realized necessary to numerical stability.Section 3 is ensured for any given incremental time, often
The variation of a unit volume strain does not exceed corresponding ef0.1%.This method is searched on each unit to find Δ t
Minimum value, the use of the value is then that all units timely update the consolidation process parameter of unit.
5th step calculates separately the seepage discharge for flowing in and out unit according to volume percolation flow velocity and incremental time, in turn
The new volume of computing unit；New unit void ratio is obtained according to unit initial volume, initial void ratio and new volume；According to list
First new volume computing unit new angular coordinate, node coordinate and element thickness, and then all element thicknesses are superimposed to obtain
To new soil body height, the difference of initial soil body height and new soil body height is settling amount.Specifically, according to the body of unit
New unit volume can be calculated in product percolation flow velocity and incremental time, and specific calculate uses following formula:
After obtaining new unit volume, according to formulaCalculate new unit void ratio；Meter
New angular coordinate, node coordinate and element thickness；Obtained element thickness is superimposed available new soil body height, newly
Soil body height and initial soil body height between difference be settling amount.
The final settlement of 6th step, soil body primary consolidation can be calculated by final void ratio, finally be sunk in the present embodiment
Drop amount is 0.037164 meter, and the ratio of settling amount and final settlement is the average degree of consolidation of the soil body, if every step or every setting
Associated arguments during dry step output soft soil consolidation, and judge whether the average degree of consolidation obtained reaches predetermined average degree of consolidation
99.99%, if reaching, calculating terminates；Otherwise third step is gone to.Specifically, the parameter in saturated soft soil consolidation process includes
The total volume of void ratio distribution, soil body settling amount, soil body height, each unit coordinate, each unit thickness, pore water pressure, the soil body
Seepage discharge, average super quiet pore pressure, average degree of consolidation etc. change with time.
Curve that the soil solidifying degree that the present invention predicts changes over time is as shown in figure 4, as seen from Figure 4, this hair
Bright prediction result is consistent with laboratory test measured data variation tendency, and numerical value difference is minimum therefore provided by the invention pre-
Survey method acquired results and test measured data are very close, and then show that the precision of prediction of this method is higher.
Specific embodiment two: apply vacuum load and preloading, vacuum along well loss, linear constitutive relation, with data point pair
Form describes constitutive relation, small deformation
Indraratna in 2005, which is established, considers vacuum and preloading and vacuum along the small strain radial consolidation of well loss
Analytic solutions have compared with high-impact, below compare calculated result of the present invention and Indraratna2005 vacuum analysis solution.
Step 1: Soil Parameters are arranged and establish model according to example actual conditions.Soil body elemental height 10m；Do not consider
Soil body self weight is Gs=1；Top, bottom boundaries head are identical as soil body height；Vertical drainage plate equivalent redius rw=0.05m；Equivalent shadow
Ring radius re=0.5m；Smear zone radius rs=0.2m；Setting vertical shaft can drain, and coboundary can not drain；Coboundary be etc. answer
Change condition；Initial vertical effective stress σv′i=1kPa, initial void ratio ei=2；Seepage flow obeys Darcy's law, smear zone outer diameter
To osmotic coefficient kh=5e-9m/s, smear zone osmotic coefficient ratio kh/ks=2；The coefficient of consolidation is chThus=3.058e-7 must be pressed
Contracting factor alphav=0.005kPa-1, this constitutive relation described in the form of data point pair.Instantaneous preloading Q=0.03kPa, applies
Vacuum -0.03kPa in well, vacuum are linearly reduced along well, drain bar bottom vacuum -0.015kPa, and setting calculates termination condition and is
The degree of consolidation reaches 99.9%.
Model, is vertically divided into 20 units by second step, and smear zone is radially divided into 16 units, smear zone outer radial
It is divided into 34 units, and the initial volume of computing unit, initial void ratio and final void ratio.
Third step, calculate each unit angular coordinate, node coordinate, element thickness, the vacuum load at certain moment and preloading,
Total stress, effective stress, infiltration coefficient, gross head, hydraulic gradient and volume percolation flow velocity.
The vertical coordinate of the angle point of each unit is calculated according to following formula:
The vertical coordinate of each node is calculated according to following formula:
The thickness of unit is calculated by following formula:
The preloading at certain moment is uniformly distributed under the conditions of iso-stress, can be obtained by following formula:
t2, t1By user define when m- payload data point to acquisition, instantaneous heap in the present embodiment
It carries and maintains 0.03kPa constant, described with (0,0), (0,0.03) two o'clock.
This embodiment is to wait strained conditions, and preloading adjusted is calculated according to following formula
The present embodiment considers that application vacuum condition, the serious null value of the well at certain moment are calculated according to following formula:
tv1, tv2By user define when m- vacuum data point to acquisition, in this example with (0,0),
(0, -0.03) two o'clock describes.
Consider vacuum along well loss, generally assume that vacuum is reduced from Jing Ding to lower linear, then in well certain position vacuum
Value is calculated according to following formula:
J is vertical drainage Board position vertex ticks, and vacuum reduction coefficient k is 0.5, L in this embodimentdFor vertical drainage plate
Driving depth.
The present embodiment applies vacuum in well, and the total stress at node i j calculates are as follows:
The void ratio of unit is calculated according to following formula:
The effective stress of unitAnd infiltration coefficientIt is closed according to the void ratio of unit at this time in this structure of multistage linear
It is that interpolation obtains in curve.
Pore pressureIt is the difference of total stress and effective stress
Super quiet pore pressure is the difference of pore pressure Yu hydrostatic pore pressure:
Deformation makes vertical infiltration coefficientDeviate original vertical infiltration coefficientIt is oval using infiltration coefficient,'s
Value is calculated as
Node i j and node i, the vertical equivalent coefficient of permeability between j+1It is expressed as
In top boundaryBottom boundary
If seepage flow follows Darcy's law and non-darcy index stream mode, from unit ij to unit i, the vertical body of j+1
Product flow rateIt can be expressed generally as
The obedience Darcy's law of the present embodiment seepage flow, therefore β=1.
Vertical hydraulic gradientIt is expressed as
The gross head of each node is calculated according to following formula:
Lower limits can not drain, then lower boundary hydraulic gradient
Upper bound can not drain, then coboundary hydraulic gradient
Corresponding expression formula is used for computing unit ij and i+1 below, the Radial Flow rate between j:
In gully
It is complete infiltration gully in the present embodiment, applies vacuum in well, then vertical shaft is with soil body intersection hydraulic gradient:
In formulaRefer to the vacuum values in vertical unit j corresponding well at position.
It is in gully and soil body intersection Radial Flow rate calculations
Seepage flow does not occur for soil body outer boundary, i.e.,
4th step, the incremental time for taking the minimum value in the incremental time of all units to calculate as a time step, into
And obtained incremental time is superimposed with current consolidation time to obtain new total consolidation time.Specifically, it counts according to the following formula
Calculate the incremental time of each time step:
It the use of the value is that all units timely update consolidation process parameter.
5th step calculates separately the seepage discharge for flowing in and out unit according to volume percolation flow velocity and incremental time, in turn
The new volume of computing unit；New unit void ratio is obtained according to unit initial volume, initial void ratio and new volume；According to list
First new volume computing unit new angular coordinate, node coordinate and element thickness, and then all element thicknesses are superimposed to obtain
To new soil body height, the difference of initial soil body height and new soil body height is settling amount.Specifically, according to the body of unit
New unit volume can be calculated in product percolation flow velocity and incremental time, and specific calculate uses following formula:
After obtaining new unit volume, new unit void ratio is calculated；Calculate new angular coordinate, node coordinate and unit
Thickness；Obtained element thickness is superimposed available new soil body height, between initial soil body height and new soil body height
Difference be settling amount.
The final settlement of 6th step, soil body primary consolidation can be calculated by final void ratio, finally be sunk in the present embodiment
Drop amount is 0.000875 meter, and the ratio of settling amount and final settlement is the average degree of consolidation of the soil body, if every step or every setting
Associated arguments during dry step output soft soil consolidation, and judge whether the average degree of consolidation obtained reaches scheduled average consolidation
Degree 99.9%, if reaching, calculating terminates；Otherwise third step is gone to.Specifically, the parameter in saturated soft soil consolidation process includes
The total volume of void ratio distribution, soil body settling amount, soil body height, each unit coordinate, each unit thickness, pore water pressure, the soil body
Seepage discharge, average super quiet pore pressure, average degree of consolidation etc. change with time.
Shown in curve such as Fig. 5 (a) that the soil solidifying degree that the present invention predicts changes over time, the averagely super quiet pore pressure of the soil body
Shown in the curve changed over time such as Fig. 5 (b), as seen from Figure 5, prediction result of the invention and Indraratna 2005
Analytic solutions calculated result variation tendency is consistent, and numerical value difference it is minimum, therefore prediction technique acquired results provided by the invention with
Analytic solutions are very close, and then show that the precision of prediction of this method is higher.But this embodiment final settlement is minimum, i.e. the example
For small strain solidification problem；2005 vacuum analysis solution of Indraratna only can be carried out that small deformation, constitutive relation be linear, true in well
The radial consolidation that empty, seepage flow is Darcy Flow, load is constant, vertical shaft punches soil layer calculates, and prediction technique provided by the invention is removed
Other than this it is also conceivable to big strain, Non-Darcy's flow, constitutive relation is non-linear, well is interior and native serious sky, vacuum and preloading at any time
Between variation, vertical shaft do not punch the factors such as soil layer, vertical and Radial Flow Through Porous Media.
The infall process prediction technique of vertical drainage plate consolidation saturated soft soil provided by the invention, has comprehensively considered the soil body
It is coboundary iso-stress and equal strained conditions, big strain (geometrical non-linearity), the effect of weight of soil, Non-Darcy's flow, vertical and radial
Vacuum can not punch along well loss, vertical shaft in seepage flow, native film coating perfonnance, the vacuum load changed over time and preloading, well
Soil layer, soil material parameter is non-linear and anisotropy etc., efficiently reduce calculating error, improve computational accuracy；And
Soil Constitutive Relation can select arbitrary form according to user's wish, this is solved, and material parameter selection is improper to be caused to calculate knot
Fruit error is larger, is difficult to practical problem under complex engineering environment.Calculating section is saved with code form, then only needs to provide meter
Parameter needed for calculating is the infall process of predictable vertical drainage plate consolidation saturated soft soil.
As it will be easily appreciated by one skilled in the art that the foregoing is merely illustrative of the preferred embodiments of the present invention, not to
The limitation present invention, any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should all include
Within protection scope of the present invention.
Claims (8)
1. a kind of infall process prediction technique of vertical drainage plate consolidation saturated soft soil, which comprises the steps of:
Step 1 is arranged the constitutive relation data point of the soil model of saturated soft soil, boundary condition, geometrical condition, changes over time
Vacuum load and preloading, Non-Darcy's flow index and calculate termination condition；
The soil model is divided into intended radial, vertical number by inside and outside smear zone according to the setting of the first step by step 2
Annular element, and calculate initial volume, initial void ratio and the final void ratio of the unit；
Step 3, according to the data that step 2 obtains, the angular coordinate of computing unit, node coordinate, element thickness, certain moment it is true
The vacuum of each position, the total stress of the unit, effective stress, infiltration are in well after empty load and preloading, consideration vacuum leak
Number, pore water pressure, gross head, hydraulic gradient and volume percolation flow velocity；
Step 4, the incremental time for taking the minimum value in the incremental time of all units to calculate as a time step, and then will
To incremental time be superimposed with current consolidation time to obtain new total consolidation time；
Step 5 calculates the volume seepage discharge for flowing in and out unit according to volume percolation flow velocity and incremental time, and then can calculate
The new volume of unit；New unit void ratio is obtained according to unit initial volume, initial void ratio and the new volume of unit；According to list
First new volume can calculate the angular coordinate, node coordinate, element thickness of unit；And then all element thicknesses are superimposed to obtain
The difference of new soil body height, initial soil body height and new soil body height is settling amount；
Step 6, is calculated soil body primary consolidation final settlement by final void ratio, and the ratio of settling amount and final settlement is
The sedimentation average degree of consolidation of the soil body；Judge whether the total consolidation time obtained or the average degree of consolidation reach scheduled total solid
Time or scheduled average degree of consolidation are tied, if reaching, end loop is calculated, and otherwise goes to step 3.
2. a kind of infall process prediction technique of vertical drainage plate consolidation saturated soft soil as described in claim 1, feature exist
In, in step 1, setting soil layer elemental height H0；Soil particle specific gravity Gs；Vertical drainage plate squeezes into soil depth Ld；Gully is equivalent
Radius rw；Smear zone equivalent redius rs；Gully Equivalence effects radius re；Boundary condition is set, i.e., whether each boundary drain, on
Strain or the iso-stress conditions such as boundary is；Specify initial overlying burden or initial void ratio；Seepage flow can obey Darcy's law or not
It obeys, i.e. setting Non-Darcy's flow index β；By volume of data point to setting constitutive relation, setting consolidates index C againrTo locate
Manage unloading/reloading；Provide soil model top and bottom hydrostatic level height；By volume of data point to providing vacuum load
It changes with time relationship with preloading；Provide the reduction form of vacuum in well；In terms of the degree of consolidation or the setting of consolidation time form
Calculate termination condition.
3. a kind of infall process prediction technique of vertical drainage plate consolidation saturated soft soil as claimed in claim 1 or 2, feature
It is, in step 2, soil model is first subjected to dividing elements according to the data of the first step, the number of unit vertically divided is Rj,
The number of unit radially divided is Ri, the number of unit wherein radially divided in smear zone is Rs, the list of smear zone outer radial division
First number is Ri-Rs, and provide smear zone osmotic coefficient ratio kh/ks；According to the initial volume V of cell geometry computing unit0,i；Root
The initial total stress of top layer's unit is obtained according to initial overlying burden and soil body self weight, is consolidated in t < 0 and is not yet started, therefore is initial
The difference of total stress and hydrostatic pore pressure is initial effective stress, the void ratio that cyclic approximation is matched on compression curve
And effective stress, by upper unit void ratio updating unit saturated unit weight, successively calculate from top to bottom whole units it is initial
Void ratio and initial effective stress；Then the final effective stress of computing unit and final void ratio, when the excess pore water of each unit
It is believed that soil body primary consolidation is completed when pressure no longer dissipates, i.e., after plus generalized load and initial effective stress superposition calculation obtain most
Whole effective stress, and then obtain the final effective stress of unit after the completion of soil solidifying, then obtained further according to soil body-shield machine system
The final void ratio of unit out.
4. a kind of infall process prediction technique of vertical drainage plate consolidation saturated soft soil as claimed in claim 3, feature exist
In the final thickness of unit is calculated according to the following formula:
L in formulafFor unit final thickness；LoFor unit original depth；efFor unit final void ratio, eoFor the initial hole of unit
Than；By the final height of the final thickness of all units soil body that is overlapped that you can get it, the elemental height of the soil body and final high
Difference between degree is soil body final settlement.
5. a kind of infall process prediction technique of vertical drainage plate consolidation saturated soft soil as claimed in claim 4, feature exist
In in step 3, it is assumed that soil model outmost turns annular element cross section in consolidation process remains rectangle, ignores horizontal direction
Strain, remaining element cross section after consolidation starts are parallel trapezoidal of vertical edges, then the vertical coordinate of the angle point of each unit according to
Following formula calculates:
Wherein, j=1,2,3 ..., Rj；I=1,2,3 ..., Ri；
Indicate the volume of t moment unit ij,
riFor the radial coordinate of node, Δ riFor the radial width of unit,
r1=ri-Δri/ 2, r2=ri+Δri/2；
The vertical coordinate of each node is calculated according to following formula:
The thickness of unit is calculated by following formula:
The preloading at certain moment is uniformly distributed under the conditions of iso-stress, can be obtained by following formula:
t2、t1By when m- payload data point to acquisition；
For equal strained conditions, preloading adjusted is calculated according to following formula:
Wherein, zavgFor soil body average height,
η is the ratio of total preloading and the preceding total preloading of adjustment after adjustment,
For radial markings be i unit t moment top preloading；Circulation adjustment is until the strain standard such as satisfaction；
The serious null value of the well at certain moment is calculated according to following formula:
tv1、tv2By when m- vacuum data point to acquisition；
Consider vacuum along well loss, the functional form of vacuum reduction can be set, it is assumed that vacuum is reduced from Jing Ding to lower linear,
Then the vacuum values of certain position are calculated according to following formula in well:
Wherein, j is vertical drainage Board position vertex ticks, and k is vacuum reduction coefficient, LdFor vertical drainage plate driving depth；
If the vacuum values of each position in well can be measured, can directly give
When not applying vacuum, the total stress at node i j is calculated according to following formula:
When a vacuum is applied, the total stress at node i j calculates are as follows:
In formula,For total stress of the unit ij in total consolidation time t；γwFor the severe of water；It is consolidated for unit im always
Soil body saturated unit weight when time t；htFor hydrostatic level height；For soil body saturated unit weight of the unit ij in total consolidation time t；
qoFor initial overlying burden, and the soil body has consolidated completion when t < 0 under this load,To be designated as the unit of i under radial direction in t
Preloading at the top of the soil body at moment；
The void ratio of unit is calculated according to following formula:
In formula,For void ratio of the unit ij in total consolidation time t+ Δ t；eo,jFor the initial void ratio of unit j；
For volume of the unit ij in total consolidation time t+ Δ t；V0,iThe unit initial volume of i is designated as under；
The effective stress of unitAnd infiltration coefficientIt is bent in multistage linear constitutive relation according to the void ratio of unit at this time
Interpolation obtains in line；
Pore pressureIt is the difference of total stress and effective stress:
Super quiet pore pressure is the difference of pore pressure Yu hydrostatic pore pressure:
Deformation makes vertical infiltration coefficientDeviate original vertical infiltration coefficientIt is oval using infiltration coefficient,Value meter
It calculates are as follows:
WhereinIt is the horizontal direction of t moment unit ij and the angle of original vertical direction；
Equivalent coefficient of permeability is for describing seepage flow between unit, node i j and node i, the vertical equivalent infiltration between j+1 between unit
CoefficientExpression are as follows:
In top boundaryBottom boundary
If seepage flow follows Darcy's law and non-darcy index stream mode, from unit ij to unit i, the vertical volume flow of j+1
Dynamic rateIt can be expressed as:
Wherein β is Non-Darcy's flow index, β=1 when seepage flow obeys Darcy's law；
Vertical hydraulic gradientExpression are as follows:
The gross head of each node is calculated according to following formula:
If lower limits can drain, lower boundary hydraulic gradient:
Otherwise
If upper bound can drain, the coboundary hydraulic gradient when not applying vacuum:
When only applying vacuum in well:
When applying in well with vacuum at the top of the soil body:
In formula,Refer to vacuum values at the top of the soil body；If upper bound does not drain
Radial Flow rate between unit ij and i+1, j:
In gully
Gully is permeated completely for one, and when not adding vacuum, vertical shaft is with soil body intersection hydraulic gradient:
Hydraulic gradient when a vacuum is applied:
In formula,Refer to the vacuum values in well at certain position；
Gross head is taken as h in partial penetration gullyt；To H not plus when vacuum0-z0,1,j≤LdPart, hydraulic gradient are as follows:
To H0-z0,1,j> LdPart,Matching test (27) modifies formula (28) when applying vacuum；
In gully and soil body intersection Radial Flow rate calculations are as follows:
Seepage flow does not occur for soil body outer boundary, i.e.,
6. a kind of infall process prediction technique of vertical drainage plate consolidation saturated soft soil as claimed in claim 5, feature exist
In calculating the incremental time of each time step according to the following formula in step 4:
In formula,To calculateThe compressed coefficient；ef,jFor unit ij final void ratio；
It is searched on each unit to find the minimum value of Δ t, the use of the minimum value is then that all units timely update unit
Parameter.
7. a kind of infall process prediction technique of vertical drainage plate consolidation saturated soft soil as claimed in claim 6, feature exist
In in step 5, the formula for obtaining new unit volume according to the volume percolation flow velocity and incremental time of unit is as follows:
After obtaining new unit volume, new unit void ratio is calculated according to formula (11)；It is calculated according to formula (2), (3), (4) new
Angular coordinate, node coordinate and element thickness；Obtained element thickness is superimposed available new soil body height, new soil
Difference between body height and initial soil body height is settling amount.
8. a kind of infall process prediction side of vertical drainage plate consolidation saturated soft soil as described in claim 1~7 any one
Method, which is characterized in that in step 6, the parameter in saturated soft soil consolidation process includes void ratio distribution, soil body settling amount, the soil body
Highly, the total volume seepage discharge of each unit coordinate, each unit thickness, pore water pressure, the soil body, average super quiet pore pressure, Yi Jiping
The equal degree of consolidation changes with time.
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| CN116541940B (en) * | 2023-06-29 | 2023-10-13 | 中交第四航务工程勘察设计院有限公司 | Consolidation degree calculating method for different acting time of grouping drainage bodies |
| CN117172060A (en) * | 2023-09-05 | 2023-12-05 | 江苏海洋大学 | Soft soil foundation nonlinear consolidation settlement analysis method based on continuous drainage boundary |
| CN117172060B (en) * | 2023-09-05 | 2024-04-23 | 江苏海洋大学 | Soft soil foundation nonlinear consolidation settlement analysis method based on continuous drainage boundary |
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